This chapter attempts to cover the most common endocrine emergencies in the newborn period. Congenital hypothyroidism that constitutes the most important of these disorders is covered in detail in the section on thyroid. The most common metabolic abnormality in a newborn irrespective of gestational age is hypoglycemia. Its clinical features, diagnosis, and management are also covered in this chapter. The most common metabolic abnormality in a newborn irrespective of gestational age is hypoglycemia. Patients who do not respond to medical therapy frequently require surgical management in the form of near total pancreatectomy. In congenital hypopituitarism, spontaneous hypoglycemia is unusual except when there are circumstances in which the neonate is inadvertently fasted. The different diseases like neonatal hyperglycemia, hypocalcemia, and neonatal thyrotoxicosis are described with their clinical features, incidence, surgery, and management. Neonatal endocrine emergencies are among the most prominent treatable disorders in the newborn. Adrenal insufficiency and disorders of sexual differentiation are challenging disorder often requiring input from an endocrinologist.